1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * BSG helper library 4 * 5 * Copyright (C) 2008 James Smart, Emulex Corporation 6 * Copyright (C) 2011 Red Hat, Inc. All rights reserved. 7 * Copyright (C) 2011 Mike Christie 8 */ 9 #ifndef _BLK_BSG_ 10 #define _BLK_BSG_ 11 12 #include <linux/blkdev.h> 13 #include <scsi/scsi_request.h> 14 15 struct bsg_job; 16 struct request; 17 struct device; 18 struct scatterlist; 19 struct request_queue; 20 21 typedef int (bsg_job_fn) (struct bsg_job *); 22 typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *); 23 24 struct bsg_buffer { 25 unsigned int payload_len; 26 int sg_cnt; 27 struct scatterlist *sg_list; 28 }; 29 30 struct bsg_job { 31 struct device *dev; 32 33 struct kref kref; 34 35 unsigned int timeout; 36 37 /* Transport/driver specific request/reply structs */ 38 void *request; 39 void *reply; 40 41 unsigned int request_len; 42 unsigned int reply_len; 43 /* 44 * On entry : reply_len indicates the buffer size allocated for 45 * the reply. 46 * 47 * Upon completion : the message handler must set reply_len 48 * to indicates the size of the reply to be returned to the 49 * caller. 50 */ 51 52 /* DMA payloads for the request/response */ 53 struct bsg_buffer request_payload; 54 struct bsg_buffer reply_payload; 55 56 int result; 57 unsigned int reply_payload_rcv_len; 58 59 /* BIDI support */ 60 struct request *bidi_rq; 61 struct bio *bidi_bio; 62 63 void *dd_data; /* Used for driver-specific storage */ 64 }; 65 66 void bsg_job_done(struct bsg_job *job, int result, 67 unsigned int reply_payload_rcv_len); 68 struct request_queue *bsg_setup_queue(struct device *dev, const char *name, 69 bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size); 70 void bsg_remove_queue(struct request_queue *q); 71 void bsg_job_put(struct bsg_job *job); 72 int __must_check bsg_job_get(struct bsg_job *job); 73 74 #endif 75